When it comes to food, everybody’s got an opinion. Same goes for parenting. Mix the two together and you’ve got the makings of a culture war. Witness the recent scuffle between Sarah Palin and Michelle Obama over the White House’s rather tame Let’s Move campaign aimed at ending childhood obesity.

So last month, when the Center for Science in the Public Interest announced it was filing a class action lawsuit to stop McDonald’s from using Happy Meal toys to market to children, the fierce and ugly backlash against the mother of two who was brave enough to attach her name to the case was predictable.

But I am not interested in debating good or bad parenting. Nor am I interested in arguing over whether this lawsuit is a good idea. How many calories are in a Happy Meal and whether you can ask for carrots instead of fries is irrelevant to me. I am not even going to give you all the scary data about how America’s kids are getting fatter and sicker. Nor do I care whether the cause is fast food or video games.

That’s all been done. Instead, let’s talk law. Because that minor detail seems to have eluded most of the national conversation about how food companies market to children.

Our legal system does not allow marketers to advertise just as they wish, either to children or adults. We have consumer protection laws because marketers aren’t exactly trustworthy. From time to time, they’ve been known to stretch the truth.

That’s why both at the federal and state levels, the law requires that advertisers not engage in deceptive marketing. Otherwise, they would have an unfair advantage over consumers. In other words, the law aims to provide a level playing field between the two parties. The key legal terms here are “deceptive” and “unfair.” Bear with me; I am saving you three years of law school and a grueling bar exam, not to mention years of debt.

Now, what about marketing to children? Ample science, along with statements by various professional organizations tells us that marketing to young children is both deceptive and unfair. Why? Because young children simply do not have the cognitive capacity to understand that they are being marketed to; they cannot comprehend “persuasive intent,” the linchpin of advertising. Here’s how the nation’s trade group for kids’ doctors puts it: “The American Academy of Pediatrics considers advertising directly to young children to be inherently deceptive, and exploits children under the age of 8 years.”

So, if advertising to young children is inherently deceptive, and deceptive advertising is illegal under federal law and in most states, how is it even happening? And doesn’t this mean that not just food, but all marketing to young children is currently illegal? I get this question a lot. The answer is yes.